Finger for loom dobbies



Nov. l, 1927.

W. H. NEEDHAM FINGER FOR LOOM DOBBIES Filed FebE 4, 1926 ZNVE/vfor:

IAM/fm H NEEM/1am @MMV 60 63a G0 4free ')as` Patented Nov. 1, 1927.

UNITED STATES PATENT OFFICE.

WILLIAM I-I. NEEDHAM, OF WORCESTER, MASSACHUSETTS, ASSIGNOR T0 CROMPTON & 'KNGWLES LOOM WORKS, OF WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

FINGER FOR LOOM DOBBIES.

Application filed February 4, 1926. Serial No. 86,062.

This invention relates to an improved finger for loom dobbies and it is the principal object of the invention to provide a multi-part finger having portions of reduced thickness to cooperate with a guiding comb and having other parts hardened to cooperate with the pegs of the dobby chain.

Loom dobbies ordinarily employ harness levers which are actuated by.- dobby back levers pivotally connected to thevharness levers at their central portions. The upper ends of the back levers are provided with one set of hooks `and the'lower ends with another set of hooks, the hooks being con.- trolled by pattern mechanism as to position so that selected hooks will be moved outwardly by a regularly reciprocating knife. The pattern mechanism usually comprises a chain formed of a series of wooden bars in which are secured hardened steel pegs. The intermediate devices between the pattern mechanism and the hooks include so-called dobby fingers which are provided on their under sides with grooves to receive the pegs and are provided with inwardly extending ends arranged either to have direct engagement with the lower hooks or to engage lifting rods for the upper hooks. My present invention relates particularly to these fingers, and it is an important objectof the invention to form the finger of pressed steel parts one of which is extended to form a guide for the comb and another ofwhich is hardened to cooperate with the hardened pegs of the pattern chain. When this latter part is hardened it is subject to slight warping or twisting, and it is a further object of the invention to hold the tempered peg run between heavier parts of the linger which are strong enough to straighten the warped runs. As a matter of convenience the run is made of relatively thin stock folded on itself, the run bending easily because of its thinness to be held in proper alingment with the pegs.

With these and other objects in view which will appear as the description proceeds, my invention resides in the combination' and arrangement of parts hereinafter described and set forth in the claims.

In the accompanying drawings 'wherein I have shown a convenient embodiment of my invention,- l

Fig. i is aliagraminatie View showing portions tif dobby'as they appear from the rear of the loom with my invention applied thereto,

Fig. 2 is a rear elevation of the finger,

Figs. 3 and i are vertical transverse sec* tions on lines 3-3 and 4*-4, respectively, of Fig. 2,

Fig. 5 is a top plan view of the finger,

Fig. 6 is a plan of the blank for the outside section before the same is bent,

Fig. 7 is a plan of the blank for the central section,

Fig. 8 isa side elevation of the run for the dobby pegs formed of hardened steel,

Fig. 9 is a view of the inner end of the dobby showing the method of bending the hook lifting arm, and

Fig. 1'0 is a fragmentary planr view of the finger separating comb taken in the direction of arrow 10, Fig. 1.

Referring particularly to Fig. 1 it will be seen that the dobby comprises a harness lever 2O pivoted on. a fixed pin 21 and having attached thereto as at 22 al dobby back lever 23. The latter has attached to the upper portion thereof a hook 24 which cooperates with a reciprocating knife 25 and has attached at the bottom thereof a Second hook 26 which cooperates with a reciprocating knife .27. The knives 25 and 27 are connected so as to work in opposite directions simultaneously and fixed stops 28 engage the upper and lower ends of the levers 23 to limit movement thereof to the left as shown in Fig. 1. The hooks may rest on cross bars 29 when lowered to be engaged by the knives.

A dobby cylinder 30 is rotatably mounted on a shaft 31 and receives regular intermittent angular movement of such degree that at each pick of the loom a new dobby chain bar 32 will be brought into operative position with respect to the dobby linger to be described. Said chain bars are provided with pegs 83 of hardened steel which serve to indicate which hooks are to be lowered into contact with the knives. A guiding vcomb comprises a fixed bar 34 having upwardl'yextending spaced wires 35 which are spacedapart a distance substantially equal to the thicknessV of the fingers and the distance between adjacent pegs on the bars 32, as shown in Fig. 10. A rod 36 is provided for supporting the dobby fingers and upf were displacement of the naa is prevented arid 37 held in fixed position;

f tions 54 and is recessed as at 55, said blank also being provided with relatively narrow arm elements 56. The central portion 52 is provided with a lifting arm element 57 similar in form to the arm elements 56 and 7 is also provided with a bearing portion 53 Lil ' section 53 shown in Fig. 8. Y as shown in Fig. 3 is formed of relatively corresponding to the bearing portion 5ft. The opposite end of the section 52 is provided with an enlarged wing 59 to lie between adjacent wires or dents 35. rl`he under side of the section 52 is cut away as indicated in Fig. 7 and is provided with inwardly extending slots 60 which receive the projecting lugs 61 formed on the peg run Said section 53 thin stock and is folded on itself, the lower free ends being flared or spread apart as at 62 to form a guide for the pegs 33.

In assembling` after the section 53 has been folded to the form shown in Fig. 3, the lugs 61 are placed in slots 60 of section 52, said lugs 61 preventing downward displacement of the section 53. Upward displacement of said section is prevented by the edge 63 which engages the upper folded side of section 53. The outer portion 51 is then folded along the line indicated at L in Fig. 6 around the sections 52 and 53, a portion of wing 59 extending through slot 55 and the lifter arm `element 57 lying between and in alignment with the lifter arm elements 56. The opposite sides of the section 51 therefore prevent lateral movement of the peg run section 53 so that the latter is held very tightly in place against displacement in any direction. rIhe parts may then be spot welded at the points indicated at IV in Fig. 2.

rIhe partsare then in the position shown in Fig. 9 and in order to provide the proper form for those fingers which engage the lower set of hooks the elements 56 and 57 are bent from the full to the dotted line position shown in Fig. 9, the dotted line position being the ultimate form of the lifting arm as shown in Figs. 1 and 2. This procedure is necessary because the upper end of the arm must lie above the fold in section 51.

Fig. 1 shows dobby fingers of two forms, the form described hereinbefore being for the lower set of hooks while the other form is indicated at and has the inwardly extending portion thereof straight to enga e the lifter rods 71 for the upper set of oolrs. In other respects the fingers are identical.

The peg run section 53 is preferably case hardened or otherwise provided with a hard surface and it not infrequently happens that the heat treatment results in warping of said section 53 so that the same requires straightening but it will be seen that inasmuch as said section is relatively sniallthe larger and stronger parallel sides of the folded section 51 will be sufiicient to hold said peg run section 53 substantially straight.

From the foregoing it will be seen that I have provided a dobby finger of pressed steel having a separate run for the 'dobby heads formed of hardened steel held to the other sections of the finger and that one of the component parts of the finger is extended to form a wing to extend between the wires 35 of the comb. It will also be seen that the peg run is relatively small and of comparatively thin stock so that any slight warping resulting from the heat treatment can be corrected by the sides of the relatively heavier section 51. It will also be seen that the hook lifting arm of the finger 50 is bent beyond the line of folding after the elements 56 and 57 are welded together.

Having thus described my invention, it will be apparent that changes and modifications may be madet-herein by those skilled in the art without departing from the spirit and scope of the invention, and I do not wish to be limited to the details herein disclosed, but what I claim is:

1. A dobby finger for looms having a pattern chain provided with pegs and a separating comb, said finger being formed of a plurality of flat sections, one of said sections extending between the dents of the comb, another of said sections being formed with a peg engaging run and being held by the iir-st section against vertical displacement, and another of said sections being bent around the first two sections and engaging the same to increase the thickness of the finger and also hold the second named section against displacement transversely of the first named section.

2. A dobby finger for looms having a pattern chain provided with pegs and a separating comb, said finger being formed of a plurality of fiat sheet metal sections, one of said sections having an extension in the form of a wing for the comb, another of said sections being folded on itself and having a peg engaging run, and means to hold said parts together to prevent relative displacement of one part with respect to the other.

3. A. dobby nger for looms having a pattern chain provided with pegs and a separating comb, said finger being formed of a plurality of fiat sheet metal sections, one section being extended to engage the comb, another section being bent on itself and having engagement with the first named part to prevent relative movement of said parts in the plane of said sections, and a surrounding member lying on both sides of said sections to restrain lateral relative movement thereof and to increase the thickness of the finger..

et. A dobby finger for looms having a pattern chain provided With pegs and a separating comb, said dobby being formed of a plurality of fiat sheet metal sections one of Which has a Wing formed therewith of a single thickness to cooperate with the comb, another section being formed with a run for the pegs, interengaging lugs on said sections to prevent relative movement thereof in the plane of the sections, and a surrounding retaining member enclosing the sections to prevent relative lateral movement thereof.

5. A dobby finger for looms having a pattern chain provided With pegs and a separating comb, said nger being formed of a plurality of sheet metal sections, one section being extended to engage the comb, anotherv section being held to the first named section against movement in a direction parallel to the plane of the first named section and having a peg receiving groove on the under side thereof, a third section folded around the first and second named sections to restrain lateral relative movement thereof, and a lifting arm formed in part by extensions formed on the last named section being bent beyond the line of fold thereof.

6. A dobby nger for looms having a pattern chain provided with pegs, said linger being formed of a plurality of sheet metal sections, said finger having a central grooved section to receive the pegs, andan outer section folded around the central section to prevent lateral displacement of the latter.

7. A dobby finger for looms having a pattern chain provided with pegs and a separating comb, said finger having central sheet metal portions to cooperate with the comb and providing a grooved run for the dobby pegs, and an outer section struck from a single piece of metal and folded to surround a part of the central portions.

8. A dobby nger for looms having a 4pattern chain provided With pegs and a separating comb, said finger having central sheet metal portions to cooperate with the comb and providing a grooved run for the dobby pegs, and an outer section struck from a single piece of metal and folded to surround a part of the central portions, said section having extending lifting arms which are bent beyond the line of fold thereof.

9. A dobby finger for looms, said finger having central portions extended beyond the body of the finger to present a relatively thin Wing and having also a grooved peg engaging portion, and an outer section folded around the central portions to retain the same in position, said parts being Welded together.

10. A dobby finger for looms having a supporting rod and hooks, said finger being formed of a folded piece of sheet metal having bearing portions for the rod and lifting arms for the hooks, said portions and said arms being symmetrically placed With respect to the line of fold of said piece of sheet metal.

1l. A dobby finger for looms having a supporting rod, a hook and a pattern chain having lifting pegs, said fingery being former with a run section for the chain pegs and a folded piece of sheet metal having parts lying on opposite sides of the run section, said piece of sheet metal having bearing portions for the rod, lifting arms for the hook and retaining parts for the run section, said portions, arms, and parts being symmetrically disposed With respect to the line of fold of said piece of sheet metal.

l2. A blank for a. pressed metal loom dobby finger, said blank having extending arms and bearing portions and peg run portions all symmetrically disposed about the center line of fold.

13. A dobby finger for looms having chain pegs, said finger having a relatively small section of hardened steel formed With a grooved run for the chain pegs, and said finger having other portions which lie on opposite sides and in engagement with the grooved run section to hold the same against improper lateral deflection.

In testimony whereof I have hereunto afiiXed my signature.

WILLIAM H. NEEDHAM. 

